A&P 1 Chapter 6 Homework
osteocytes:
newly deposited bone
What type of bone growth do you think a 40-year-old male experiences?
Appositional growth
Which canals connect lacunae together?
Canaliculi
The root word ________ means "immature or precursor." The root word _______ means "growth." The root word _______ means "around."
-blast -physis peri-
______ allow for the passage of oxygen, nutrients, and small substances to and from osteocytes trapped within lacunae.
Canaliculi
Place the following steps of bone repair in the correct sequence.1. The bone callus is remodeled and primary bone is replaced with secondary bone.2. A hematoma fills the gap between bone fragments.3. Osteoblasts build a new bone callus.4. Fibroblasts and chondroblasts infiltrate the hematoma and a soft callus forms.
2, 4, 3, 1
Correctly order the following key steps in the process of endochondral ossification. Chondrocytes die. Osteoblasts build the bone collar on the external surface of the bone. Perichondrium is invaded by blood vessels. In the primary ossification center, osteoblasts replace calcified cartilage with early spongy bone. Perichondrial cells differentiate into osteogenic cells then into osteoblasts.
3, 5, 2, 1, 4
During bone repair, the bony callus may last up to ________________.
3-4 months
How long does bone repair generally take?
6 weeks
Which of the following structures persists for life?
Articular cartilage
Which of the following organs regulate blood calcium concentration in response to parathyroid hormone (PTH)?
Bones Small intestines Kidneys
Which hormone, produced by the thyroid gland, works opposite to parathyroid hormone (PTH)?
Calcitonin
Why are collagen fibers a critical component of bone?
Collagen fibers help bone resist twisting, pulling, or stretching forces.
If a break occurs in the shaft of a thigh bone, what part of the bone has been broken?
Diaphysis
____ is the internal layer of spongy bone in flat bones.
Diploë
______ forms bone from within a model of hyaline cartilage.
Endochondral ossification
What structure allows the diaphysis of the bone to increase in length?
Epiphyseal plate
What is NOT an effect of growth hormone?
Growth hormone promotes the closure of the epiphyseal plate.
Which of the following sequences correctly lists the order of events that occur during fracture healing?
Hematoma forms -> soft callus forms -> hard callus forms -> remodeling occurs
What is the function of red bone marrow?
Hematopoiesis
Whose bone marrow is mostly red?
Infants
Which of the following statements about bone remodeling
It occurs in response to stress and tension on a bone. It occurs throughout life. It only occurs if there is low blood calcium levels.
When considering the classification of bones, which bones are used primarily for movement rather than protection?
Long bones
Which of the following events happens during intramembranous ossification?
Mesenchymal cells differentiate into osteoblasts.
Which of the following functions is associated with the skeletal system?
Movement
______ is the process of bone formation.
Ossification
_____ produce new bone tissue by secreting matrix.
Osteoblasts
Bones are constantly undergoing resorption for various reasons. Which of the following cells accomplishes this process?
Osteoclast
Which type of cell forms the medullary cavity in a fetal bone and removes excess bone at a fracture site?
Osteoclast
______ is a loss of bone mass.
Osteoporosis
Which of the following hormones inhibits bone growth?
Parathyroid hormone
What hormone promotes an increase in the activity of osteoclasts?
Parathyroid hormone (PTH)
_______ run perpendicular to the osteons.
Perforating canals
Which of the following factors promotes bone resorption?
Pressure
Which of the following is a major difference between primary and secondary bone?
Primary bone has irregularly arranged collagen bundles, while secondary has regularly arranged ones. Primary bone is not as strong as secondary bone. Primary bone does not have fully formed lamellae while secondary bone does.
Which vitamin is important for the synthesis of collagen?
Vitamin C
Within the epiphyseal plate, which zone houses actively dividing cartilage cells in their lacunae?
Zone of proliferation
As a result of males producing more testosterone at puberty, __________.
appositional bone growth increases
The thickness of bones increase as an individual grows into adulthood by ______________.
appositional growth
Bones perform all the following functions
blood cell formation fat storage protection
The canal that runs through the core of each osteon is the site of _______________.
blood vessels and nerve fibers
For a person who starts running for exercise, __________.
bone deposition exceeds bone resorption
osteoclasts
breaking down bone
When blood calcium levels rise above normal, osteoclast activity is inhibited by the hormone ___.
calcitonin
Which of the following hormones is currently thought to decrease plasma calcium levels in pregnant women and children?
calcitonin
All of the following factors will affect osteoblast and osteoclast activity
calcitonin and parathyroid hormone levels mechanical stress. blood calcium level.
PTH promotes the formation of which hormone?
calcitriol
Which hormone works directly in the intestine to increase plasma calcium levels?
calcitriol
The main minerals bone stores are ____________________.
calcium and phosphorus
What accounts for the majority of bone (osseous) tissue matrix?
calcium salts
Bone is considered an important storage reservoir for ________________.
calcium, phosphate, and lipids
Bone growth and remodeling depends on adequate intake of __________.
calcium, vitamin C, and vitamin K
A greenstick fracture occurs primarily in _____________.
children
The major organic component of bone extracellular matrix is __________.
collagen
All of the following components are associated with the organic matrix
collagen. glycosaminoglycans. proteoglycans.
A ____ fracture results when the bone is shattered into multiple fragments.
comminuted
The hard, dense bone that forms the outer surface of bones is:
compact bone.
A patient shows up in the emergency department with the end of the bone protruding through his skin. What type of fracture does he have?
compound fractures
What effects occur to the bones of astronauts who spend a prolonged period in space?
decreased amount of compression and tension on bones and decreased osteoblast activity.
Primary ossification centers develop in long bones in the __________.
diaphysis
The long, tubular shaft of a long bone is called __________.
diaphysis
The main central shaft of a long bone is called the ______.
diaphysis
The innermost surface of bone has a lining known as the _____.
endosteum
All the following events occur during intramembranous ossification
enlargement of the medullary cavity.
Growth of a long bone occurs at a(n) ________ plate.
epiphyseal
When the cartilage at the epiphyseal plate stops dividing, the bony structure that forms is known as the _____.
epiphyseal line
Damage to the _________ in a long bone of a young person might cause the bone not to lengthen properly.
epiphyseal plate
The ________ is the enlarged, rounded end of a long bone.
epiphysis
The secondary ossification center in a long bone is located at the ____.
epiphysis
All of the following bones are formed by intramembranous ossification
femur
Thin, broad bones should be classified as:
flat bones.
Appositional growth allows bones to __________.
grow in width
Appositional growth produces __________.
growth in width
Blood cells are made in the red bone marrow of bones, a process known as __________.
hematopoiesis
Blood cells are made in the red bone marrow of bones, a process known as:
hematopoiesis.
Which of the following gives bone its strength and ability to withstand compression and protect?
hydroxyapatite crystals
Calcitonin functions to:
increase bone deposition.
Which of the following is not one of the effects of growth hormone on bones?
increase in the activity of osteoclast
Which of the following would be a way that parathyroid hormone (PTH) could alter plasma calcium levels?
increase osteoclasts increase reabsorption of calcium in the kidney
Increasing mechanical stress will cause bone to become stronger by ________________.
increasing deposition of mineral salts
If the _____ is destroyed, bone would become flexible and unable to resist compression.
inorganic matrix
Flat bones such as the bones of the skull form via __________.
intramembranous ossification
The skull and clavicle form through ________________.
intramembranous ossification
Spongy bone differs from compact bone because spongy bone
is composed of trabeculae that are oriented along lines of stress.
The patella is classified as a sesamoid bone since it:
is located within tendons.
Osteoblasts become surrounded by the extracellular matrix (ECM) and become trapped within a _____.
lacuna
Which shape of bone contains a medullary cavity and epiphyseal lines?
long
Bones with a diaphysis and epiphyses are classified as:
long bones.
Bone lengthens by _____ growth and thickens by ____ growth.
longitudinal; appositional
A(n) ________ is an immature cell involved in bone formation.
osteoblast
Which type of cell is responsible for bone deposition?
osteoblasts
Bone deposition is performed by ____, whereas bone resorption is performed by ____.
osteoblasts; osteoclasts
Bone resorption requires the activity of __________.
osteoclasts
Bone cells that are surrounded by bone matrix and are located with lacunae are ____.
osteocytes
Which sequence is correct for the of development of mature bone cells?
osteogenic cells → osteoblasts → osteocytes
Cells that develop into osteoblasts are called:
osteogenic cells.
The structural units of mature compact bone are called __________.
osteons
The structural units of mature compact bone are called:
osteons.
Which of the following hormones does NOT cause bone growth?
parathyroid hormone
The connective tissue that surrounds compact bone is the _________
periosteum.
The type of bone that has irregularly arranged collagen bundles, abundant osteocytes, and little inorganic matrix, is classified as __________.
primary bone
Bone remodeling involves all of the following factors
replacement of old bone tissue with new bone tissue. osteoblasts and osteoclasts. bone resorption and bone deposition.
Bones located within a tendon are classified as _____ bones.
sesamoid
Bones that are roughly cubed-shaped are classified as _____ bones.
short
Intramembranous ossification occurs in:
skull bones.
Out of the numerous factors that influence bone growth and remodeling, ______ do (does) not.
the amount of fibrocartilage available
Spongy bone is made up of a branching framework called ____.
trabeculae
The function of yellow bone marrow is __________.
triglyceride storage
Severe anemia may trigger an adaptive conversion of _________________.
yellow marrow to red marrow
The stacked chondrocytes undergo rapid cell division within the
zone of proliferation.
